ESTRO 2024 - Abstract Book

S1515

Clinical - Lower GI

ESTRO 2024

Figure 2. The differences of dose statistics in FA-RT and R-RT. (A) Exposure dose of bone marrow; (B) Dose distributions in other OARs; (C) Dose of targets; (D) Severity of bone marrow suppression in 11 patients who received FA-RT. **: P < 0.01, ns: no significance.

Conclusion:

Delineating BM-a and designing FA-RT according to PET/MR could reduce exposure dose to BM-a without affecting the dose distribution to targets and other OARs. No patients experienced severe myelosuppression. Therefore, PET-MR based FA-RT may better protect bone marrow hematopoiesis for rectal cancer patients with neoadjuvant radiotherapy.

Keywords: PET/MR, functional avoidance planning, bone marrow

References:

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